99 silhouette rear end knocking noise

[mbeebe1]

I get a knocking noise from the rear end of my 99 silhouette. The noise is only when hitting bumps and sound like something is loose and hitting the frame.

I have changed the air shocks and the leveling device is free and appears to work well. The air compressor doesn't rattle nor does the muffler. The spare tire doesn't rattle either.

My next try is to have my college age son ride underneath find the sound.

I found this link on the montana site for replacement shocks. The fit the original air line fittings. Unfortunately I bought the delco AC's and hand to redo the air lines. Paid more and more work.


"I just got the Monroe Max-Air 824 shocks put on last night. They bolt right up and have the same air connection nipple as the stock GM shocks. The pair cost me about $90 shipped from RockAuto.com. I had to cut the bottom bolts off because they were seized to the shock bushing, but the top bolts came off easy. The whole job took about an hour in the driveway.
The dealer told me that they have looked and never been able to find any shock other than the GM ($172.00 per shock) that will work. I did a search on the internet and verified with Monroes tech support that they would work. Saved me lots of money. These are a good replacement for anyone with the Self leveling suspension."

[PteHoward]

Similar issue in my 01 Montana. I searched high and low to end this rattle, i thought it was the liscence plate banging off the tailgate, but here is what I found! Inside the tailgate there is a metal rod going from the actuator, to the lock itself. This comes loose and rattles over sharp bumps!, Remove the tailgate handle on the inside with a torx screwdriver (i belive a 30) and gently pry the rear cover off. you will see your two speakers and a rectangular opening in the center with a dustcover over it (looks like saran-wrap). Remove this and look for a thing metal shaft. What I did, was I took some 3/4" bed foam and wrapped it around this bar all the way up and down and ziptied the hell out of it. Replace panel, and go for a drive.. Also while your back there with the tailgate closed, check the gap all the way around the tailgate and the body, if you notice some parts are touching, you can adjust the gap by rotating the rubber stops above the taillights.